1. Field of the Invention
The present invention relates to a single plate system color solid-state image pick-up device of a microlens loading type which is provided in an image input device such as a digital camera and more particularly to a single plate system color solid-state image pick-up device of a microlens loading type in which color shading is caused with difficulty and an image input device comprising the same.
2. Description of the Related Art
A single plate system solid-state image pick-up device of a CCD type or a CMOS type is loaded onto an image input device such as a digital camera. In the single plate system solid-state image pick-up device, a large number of pixels are arranged like a tetragonal lattice or a honeycomb, and a color filter for transmitting one of red (R), green (G) and blue (B) colors is laminated on each of the pixels. A microlens is loaded every pixel in such a manner that a light is efficiently incident on an opening of each pixel.
For example, in a solid-state image pick-up device described in JP-A-5-75085, a microlens is loaded every pixel, and furthermore, a shape of a corresponding microlens is changed for each color of a color filter depending on an angle of incidence from a lens optical system for collecting a light onto a tip surface of the solid-state image pick-up device onto each pixel, thereby compensating for a variation in a sensitivity unevenness generated by shading of the lens and changing a curvature of the microlens for each color of the color filter to compensate for a variation in the sensitivity unevenness.
In a recent solid-state image pick-up device, an increase in pixels has been developed and a dimension of one pixel has been reduced very greatly. For this reason, the influence of the shading of an incident light through an opening of a light receiving surface in a terminal portion of an incident optical path of each pixel (an opening of a shielding film) is greater than that of shading caused by the microlens provided on the entry of the incident optical path of each pixel. Consequently, there is a problem in that color shading is generated.